CS 757 Low FPS in Sky?

Hello :3

So, I've recently bought the CS757.  I had a clean install of FSX (it's on a new computer).  It runs pretty well on my system and settings with about 36 fps at KLAX with about 85% traffic.  I took off and was flying at about 32,000ft when I noticed that my framerate went down to about 8 fps O.o

I'm so confused xD  Shouldn't the framerate be better when I'm in the sky because it has to load less stuff?  Does anybody have any clue what's wrong?

Thanks for any advice